:root {
  color-scheme: light;
  --bg: #f5f7f6;
  --surface: #ffffff;
  --surface-soft: #eef3f1;
  --ink: #111820;
  --muted: #5f6872;
  --line: #d8dfdd;
  --accent: #0f6672;
  --accent-strong: #0b4650;
  --warning: #ffc747;
  --danger: #c22929;
  --hero: #101820;
  --shadow: 0 16px 38px rgba(11, 24, 32, 0.08);
}

* {
  box-sizing: border-box;
}

html {
  font-family: -apple-system, BlinkMacSystemFont, "Apple SD Gothic Neo", "Noto Sans KR", "Segoe UI", sans-serif;
  line-height: 1.58;
  background: var(--bg);
  color: var(--ink);
}

body {
  margin: 0;
}

a {
  color: var(--accent-strong);
  text-decoration-thickness: 1px;
  text-underline-offset: 3px;
}

img {
  max-width: 100%;
}

.site {
  min-height: 100vh;
  overflow-x: hidden;
}

.nav {
  position: sticky;
  z-index: 10;
  top: 0;
  border-bottom: 1px solid rgba(216, 223, 221, 0.78);
  background: rgba(245, 247, 246, 0.9);
  backdrop-filter: blur(14px);
}

.nav-inner,
.wrap {
  width: min(1080px, calc(100% - 40px));
  margin: 0 auto;
}

.nav-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 18px;
  min-height: 72px;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  color: var(--ink);
  font-weight: 900;
  text-decoration: none;
}

.brand-mark {
  display: block;
  width: 34px;
  height: 34px;
  border-radius: 8px;
  box-shadow: 0 8px 20px rgba(11, 24, 32, 0.14);
}

.nav-links {
  display: flex;
  gap: 16px;
  flex-wrap: wrap;
  font-size: 14px;
  font-weight: 800;
}

h1,
h2,
h3,
p,
li {
  margin-top: 0;
  overflow-wrap: break-word;
  word-break: keep-all;
}

h1 {
  margin-bottom: 16px;
  font-size: 64px;
  line-height: 1.02;
  letter-spacing: 0;
}

h2 {
  margin-bottom: 14px;
  font-size: 34px;
  line-height: 1.18;
  letter-spacing: 0;
}

h3 {
  margin-bottom: 8px;
  font-size: 19px;
}

.hero {
  position: relative;
  overflow: hidden;
  padding: 86px 0 78px;
  background: var(--hero);
  color: #fff;
}

.hero::before {
  position: absolute;
  inset: 0;
  content: "";
  background:
    linear-gradient(90deg, rgba(16, 24, 32, 0.98) 0%, rgba(16, 24, 32, 0.86) 45%, rgba(16, 24, 32, 0.5) 100%),
    url("./assets/app-preview.png");
  background-position: center, right 18% top 20%;
  background-size: cover, 420px auto;
  background-repeat: no-repeat;
}

.hero-copy {
  position: relative;
  z-index: 1;
  max-width: 720px;
}

.eyebrow {
  margin-bottom: 12px;
  color: var(--accent);
  font-size: 13px;
  font-weight: 900;
  letter-spacing: 0;
  text-transform: uppercase;
}

.hero .eyebrow {
  color: var(--warning);
}

.lead {
  max-width: 650px;
  margin-bottom: 24px;
  color: rgba(255, 255, 255, 0.78);
  font-size: 20px;
  font-weight: 600;
}

.store-note {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-bottom: 28px;
}

.store-note span {
  display: inline-flex;
  min-height: 32px;
  align-items: center;
  padding: 6px 10px;
  border: 1px solid rgba(255, 255, 255, 0.18);
  border-radius: 8px;
  background: rgba(255, 255, 255, 0.08);
  color: rgba(255, 255, 255, 0.88);
  font-size: 13px;
  font-weight: 800;
}

.actions {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 44px;
  padding: 10px 16px;
  border: 1px solid var(--warning);
  border-radius: 8px;
  background: var(--warning);
  color: #101820;
  font-weight: 900;
  text-decoration: none;
}

.button.secondary {
  border-color: rgba(255, 255, 255, 0.28);
  background: rgba(255, 255, 255, 0.1);
  color: #fff;
}

.snapshot {
  padding: 22px 0 8px;
}

.metric-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 14px;
}

.metric-card,
.feature-card,
.note-panel,
.panel {
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--surface);
  box-shadow: var(--shadow);
}

.metric-card {
  min-height: 118px;
  padding: 18px;
}

.metric-card span {
  display: block;
  margin-bottom: 10px;
  color: var(--muted);
  font-size: 14px;
  font-weight: 800;
}

.metric-card strong {
  display: block;
  color: var(--ink);
  font-size: 30px;
  line-height: 1.08;
}

.metric-card:nth-child(2) strong {
  color: var(--danger);
}

.metric-card:nth-child(3) strong {
  color: var(--accent-strong);
}

.section {
  padding: 48px 0;
}

.section-head {
  max-width: 760px;
  margin-bottom: 22px;
}

.section-head p:not(.eyebrow) {
  color: var(--muted);
  font-size: 17px;
}

.feature-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 14px;
}

.feature-card {
  min-height: 220px;
  padding: 22px;
}

.feature-card h3 {
  color: var(--ink);
}

.feature-card p {
  margin-bottom: 0;
  color: var(--muted);
}

.calm-band {
  background: var(--surface-soft);
}

.preset-band {
  background: #fff;
}

.preset-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 14px;
}

.preset-panel {
  min-height: 170px;
  padding: 24px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--surface);
  box-shadow: var(--shadow);
}

.preset-panel h3 {
  margin-bottom: 16px;
}

.preset-list {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.preset-list span {
  display: inline-flex;
  min-height: 36px;
  align-items: center;
  padding: 7px 11px;
  border: 1px solid #c7d8dc;
  border-radius: 8px;
  background: #eef8f9;
  color: var(--accent-strong);
  font-size: 14px;
  font-weight: 900;
}

.split {
  display: grid;
  grid-template-columns: 0.9fr 1.1fr;
  gap: 30px;
  align-items: start;
}

.split p {
  margin-bottom: 0;
  color: var(--muted);
  font-size: 17px;
}

.note-panel {
  padding: 28px;
}

.note-panel p {
  margin-bottom: 0;
  color: var(--muted);
}

.doc {
  padding: 42px 0 54px;
}

.doc .panel {
  padding: min(7vw, 44px);
}

.doc h1 {
  color: var(--ink);
  font-size: 42px;
}

.doc h2 {
  margin-top: 32px;
  font-size: 24px;
}

.doc p,
.doc li {
  color: var(--muted);
}

.doc ul {
  padding-left: 22px;
}

.meta {
  margin-bottom: 24px;
  color: var(--muted);
  font-size: 14px;
  font-weight: 800;
}

.footer {
  padding: 28px 0 40px;
  border-top: 1px solid var(--line);
  color: var(--muted);
  font-size: 14px;
}

@media (max-width: 900px) {
  h1 {
    font-size: 52px;
  }

  .hero::before {
    background-position: center, right -90px top 36px;
    background-size: cover, 360px auto;
  }

  .metric-grid,
  .feature-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .preset-grid {
    grid-template-columns: 1fr;
  }

  .split {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 640px) {
  .nav-inner {
    align-items: flex-start;
    flex-direction: column;
    justify-content: center;
    min-height: 92px;
    padding: 14px 0;
  }

  .nav-links {
    gap: 12px;
  }

  .hero {
    padding: 58px 0 54px;
  }

  .hero::before {
    background:
      linear-gradient(180deg, rgba(16, 24, 32, 0.96) 0%, rgba(16, 24, 32, 0.9) 56%, rgba(16, 24, 32, 0.72) 100%),
      url("./assets/app-preview.png");
    background-position: center, right -120px top 18px;
    background-size: cover, 300px auto;
  }

  h1 {
    max-width: 320px;
    font-size: 42px;
  }

  h2 {
    font-size: 28px;
  }

  .lead {
    font-size: 17px;
  }

  .metric-grid,
  .feature-grid {
    grid-template-columns: 1fr;
  }

  .metric-card {
    min-height: 96px;
  }

  .metric-card strong {
    font-size: 26px;
  }

  .feature-card {
    min-height: 0;
  }
}